Nondiabetic premenopausal women have a much lower incidence of cardiovascular disease (CVD) than men, but premenopausal women with diabetes appear to lose this advantage and may have a greater CVD risk than men. Inteventions to reduce CVD risk are therefore of great potential benefit. Our hypothesis is that in premenopausal women with niddm, exercise training will reduced CVD risk by improving lipids and lipoproteins.